diff options
Diffstat (limited to 'src/libmgcp/mgcp_network.c')
| -rw-r--r-- | src/libmgcp/mgcp_network.c | 1064 |
1 files changed, 1064 insertions, 0 deletions
diff --git a/src/libmgcp/mgcp_network.c b/src/libmgcp/mgcp_network.c new file mode 100644 index 000000000..abce6e49d --- /dev/null +++ b/src/libmgcp/mgcp_network.c @@ -0,0 +1,1064 @@ +/* A Media Gateway Control Protocol Media Gateway: RFC 3435 */ +/* The protocol implementation */ + +/* + * (C) 2009-2012 by Holger Hans Peter Freyther <zecke@selfish.org> + * (C) 2009-2012 by On-Waves + * All Rights Reserved + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU Affero General Public License as published by + * the Free Software Foundation; either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Affero General Public License for more details. + * + * You should have received a copy of the GNU Affero General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + * + */ + +#include <string.h> +#include <stdlib.h> +#include <unistd.h> +#include <errno.h> +#include <time.h> +#include <limits.h> + +#include <sys/socket.h> +#include <arpa/inet.h> + +#include <osmocom/core/msgb.h> +#include <osmocom/core/select.h> + +#include <osmocom/netif/rtp.h> + +#include <openbsc/mgcp.h> +#include <openbsc/mgcp_internal.h> + +#include <openbsc/osmux.h> + +#warning "Make use of the rtp proxy code" + + +#define RTP_SEQ_MOD (1 << 16) +#define RTP_MAX_DROPOUT 3000 +#define RTP_MAX_MISORDER 100 +#define RTP_BUF_SIZE 4096 + +enum { + MGCP_PROTO_RTP, + MGCP_PROTO_RTCP, +}; + +/** + * This does not need to be a precision timestamp and + * is allowed to wrap quite fast. The returned value is + * 1/unit seconds. + */ +static uint32_t get_current_ts(unsigned unit) +{ + struct timespec tp; + uint64_t ret; + + if (!unit) + return 0; + + memset(&tp, 0, sizeof(tp)); + if (clock_gettime(CLOCK_MONOTONIC, &tp) != 0) + LOGP(DMGCP, LOGL_NOTICE, + "Getting the clock failed.\n"); + + /* convert it to 1/unit seconds */ + ret = tp.tv_sec; + ret *= unit; + ret += (int64_t)tp.tv_nsec * unit / 1000 / 1000 / 1000; + + return ret; +} + +int mgcp_udp_send(int fd, struct in_addr *addr, int port, char *buf, int len) +{ + struct sockaddr_in out; + out.sin_family = AF_INET; + out.sin_port = port; + memcpy(&out.sin_addr, addr, sizeof(*addr)); + + return sendto(fd, buf, len, 0, (struct sockaddr *)&out, sizeof(out)); +} + +int mgcp_send_dummy(struct mgcp_endpoint *endp) +{ + static char buf[] = { MGCP_DUMMY_LOAD }; + int rc; + int was_rtcp = 0; + + rc = mgcp_udp_send(endp->net_end.rtp.fd, &endp->net_end.addr, + endp->net_end.rtp_port, buf, 1); + + if (rc == -1) + goto failed; + + if (endp->tcfg->omit_rtcp) + return rc; + + was_rtcp = 1; + rc = mgcp_udp_send(endp->net_end.rtcp.fd, &endp->net_end.addr, + endp->net_end.rtcp_port, buf, 1); + + if (rc >= 0) + return rc; + +failed: + LOGP(DMGCP, LOGL_ERROR, + "Failed to send dummy %s packet: %s on: 0x%x to %s:%d\n", + was_rtcp ? "RTCP" : "RTP", + strerror(errno), ENDPOINT_NUMBER(endp), inet_ntoa(endp->net_end.addr), + was_rtcp ? endp->net_end.rtcp_port : endp->net_end.rtp_port); + + return -1; +} + +static int32_t compute_timestamp_aligment_error(struct mgcp_rtp_stream_state *sstate, + int ptime, uint32_t timestamp) +{ + int32_t timestamp_delta; + + if (ptime == 0) + return 0; + + /* Align according to: T - Tlast = k * Tptime */ + timestamp_delta = timestamp - sstate->last_timestamp; + + return timestamp_delta % ptime; +} + +static int check_rtp_timestamp(struct mgcp_endpoint *endp, + struct mgcp_rtp_state *state, + struct mgcp_rtp_stream_state *sstate, + struct mgcp_rtp_end *rtp_end, + struct sockaddr_in *addr, + uint16_t seq, uint32_t timestamp, + const char *text, int32_t *tsdelta_out) +{ + int32_t tsdelta; + int32_t timestamp_error; + + /* Not fully intialized, skip */ + if (sstate->last_tsdelta == 0 && timestamp == sstate->last_timestamp) + return 0; + + if (seq == sstate->last_seq) { + if (timestamp != sstate->last_timestamp) { + sstate->err_ts_counter += 1; + LOGP(DMGCP, LOGL_ERROR, + "The %s timestamp delta is != 0 but the sequence " + "number %d is the same, " + "TS offset: %d, SeqNo offset: %d " + "on 0x%x SSRC: %u timestamp: %u " + "from %s:%d in %d\n", + text, seq, + state->timestamp_offset, state->seq_offset, + ENDPOINT_NUMBER(endp), sstate->ssrc, timestamp, + inet_ntoa(addr->sin_addr), ntohs(addr->sin_port), + endp->conn_mode); + } + return 0; + } + + tsdelta = + (int32_t)(timestamp - sstate->last_timestamp) / + (int16_t)(seq - sstate->last_seq); + + if (tsdelta == 0) { + /* Don't update *tsdelta_out */ + LOGP(DMGCP, LOGL_NOTICE, + "The %s timestamp delta is %d " + "on 0x%x SSRC: %u timestamp: %u " + "from %s:%d in %d\n", + text, tsdelta, + ENDPOINT_NUMBER(endp), sstate->ssrc, timestamp, + inet_ntoa(addr->sin_addr), ntohs(addr->sin_port), + endp->conn_mode); + + return 0; + } + + if (sstate->last_tsdelta != tsdelta) { + if (sstate->last_tsdelta) { + LOGP(DMGCP, LOGL_INFO, + "The %s timestamp delta changes from %d to %d " + "on 0x%x SSRC: %u timestamp: %u from %s:%d in %d\n", + text, sstate->last_tsdelta, tsdelta, + ENDPOINT_NUMBER(endp), sstate->ssrc, timestamp, + inet_ntoa(addr->sin_addr), ntohs(addr->sin_port), + endp->conn_mode); + } + } + + if (tsdelta_out) + *tsdelta_out = tsdelta; + + timestamp_error = + compute_timestamp_aligment_error(sstate, state->packet_duration, + timestamp); + + if (timestamp_error) { + sstate->err_ts_counter += 1; + LOGP(DMGCP, LOGL_NOTICE, + "The %s timestamp has an alignment error of %d " + "on 0x%x SSRC: %u " + "SeqNo delta: %d, TS delta: %d, dTS/dSeq: %d " + "from %s:%d in mode %d. ptime: %d\n", + text, timestamp_error, + ENDPOINT_NUMBER(endp), sstate->ssrc, + (int16_t)(seq - sstate->last_seq), + (int32_t)(timestamp - sstate->last_timestamp), + tsdelta, + inet_ntoa(addr->sin_addr), ntohs(addr->sin_port), + endp->conn_mode, state->packet_duration); + } + return 1; +} + +/* Set the timestamp offset according to the packet duration. */ +static int adjust_rtp_timestamp_offset(struct mgcp_endpoint *endp, + struct mgcp_rtp_state *state, + struct mgcp_rtp_end *rtp_end, + struct sockaddr_in *addr, + int16_t delta_seq, uint32_t in_timestamp) +{ + int32_t tsdelta = state->packet_duration; + int timestamp_offset; + uint32_t out_timestamp; + + if (tsdelta == 0) { + tsdelta = state->out_stream.last_tsdelta; + if (tsdelta != 0) { + LOGP(DMGCP, LOGL_NOTICE, + "A fixed packet duration is not available on 0x%x, " + "using last output timestamp delta instead: %d " + "from %s:%d in %d\n", + ENDPOINT_NUMBER(endp), tsdelta, + inet_ntoa(addr->sin_addr), ntohs(addr->sin_port), + endp->conn_mode); + } else { + tsdelta = rtp_end->codec.rate * 20 / 1000; + LOGP(DMGCP, LOGL_NOTICE, + "Fixed packet duration and last timestamp delta " + "are not available on 0x%x, " + "using fixed 20ms instead: %d " + "from %s:%d in %d\n", + ENDPOINT_NUMBER(endp), tsdelta, + inet_ntoa(addr->sin_addr), ntohs(addr->sin_port), + endp->conn_mode); + } + } + + out_timestamp = state->out_stream.last_timestamp + delta_seq * tsdelta; + timestamp_offset = out_timestamp - in_timestamp; + + if (state->timestamp_offset != timestamp_offset) { + state->timestamp_offset = timestamp_offset; + + LOGP(DMGCP, LOGL_NOTICE, + "Timestamp offset change on 0x%x SSRC: %u " + "SeqNo delta: %d, TS offset: %d, " + "from %s:%d in %d\n", + ENDPOINT_NUMBER(endp), state->in_stream.ssrc, + delta_seq, state->timestamp_offset, + inet_ntoa(addr->sin_addr), ntohs(addr->sin_port), + endp->conn_mode); + } + + return timestamp_offset; +} + +/* Set the timestamp offset according to the packet duration. */ +static int align_rtp_timestamp_offset(struct mgcp_endpoint *endp, + struct mgcp_rtp_state *state, + struct mgcp_rtp_end *rtp_end, + struct sockaddr_in *addr, + uint32_t timestamp) +{ + int timestamp_error = 0; + int ptime = state->packet_duration; + + /* Align according to: T + Toffs - Tlast = k * Tptime */ + + timestamp_error = compute_timestamp_aligment_error( + &state->out_stream, ptime, + timestamp + state->timestamp_offset); + + if (timestamp_error) { + state->timestamp_offset += ptime - timestamp_error; + + LOGP(DMGCP, LOGL_NOTICE, + "Corrected timestamp alignment error of %d on 0x%x SSRC: %u " + "new TS offset: %d, " + "from %s:%d in %d\n", + timestamp_error, + ENDPOINT_NUMBER(endp), state->in_stream.ssrc, + state->timestamp_offset, inet_ntoa(addr->sin_addr), + ntohs(addr->sin_port), endp->conn_mode); + } + + OSMO_ASSERT(compute_timestamp_aligment_error(&state->out_stream, ptime, + timestamp + state->timestamp_offset) == 0); + + return timestamp_error; +} + +int mgcp_rtp_processing_default(struct mgcp_endpoint *endp, struct mgcp_rtp_end *dst_end, + char *data, int *len, int buf_size) +{ + return 0; +} + +int mgcp_setup_rtp_processing_default(struct mgcp_endpoint *endp, + struct mgcp_rtp_end *dst_end, + struct mgcp_rtp_end *src_end) +{ + return 0; +} + +void mgcp_get_net_downlink_format_default(struct mgcp_endpoint *endp, + int *payload_type, + const char**audio_name, + const char**fmtp_extra) +{ + /* Use the BTS side parameters when passing the SDP data (for + * downlink) to the net peer. + */ + *payload_type = endp->bts_end.codec.payload_type; + *audio_name = endp->bts_end.codec.audio_name; + *fmtp_extra = endp->bts_end.fmtp_extra; +} + + +void mgcp_rtp_annex_count(struct mgcp_endpoint *endp, struct mgcp_rtp_state *state, + const uint16_t seq, const int32_t transit, + const uint32_t ssrc) +{ + int32_t d; + + /* initialize or re-initialize */ + if (!state->stats_initialized || state->stats_ssrc != ssrc) { + state->stats_initialized = 1; + state->stats_base_seq = seq; + state->stats_max_seq = seq - 1; + state->stats_ssrc = ssrc; + state->stats_jitter = 0; + state->stats_transit = transit; + state->stats_cycles = 0; + } else { + uint16_t udelta; + + /* + * The below takes the shape of the validation of + * Appendix A. Check if there is something weird with + * the sequence number, otherwise check for a wrap + * around in the sequence number. + * It can't wrap during the initialization so let's + * skip it here. The Appendix A probably doesn't have + * this issue because of the probation. + */ + udelta = seq - state->stats_max_seq; + if (udelta < RTP_MAX_DROPOUT) { + if (seq < state->stats_max_seq) + state->stats_cycles += RTP_SEQ_MOD; + } else if (udelta <= RTP_SEQ_MOD - RTP_MAX_MISORDER) { + LOGP(DMGCP, LOGL_NOTICE, + "RTP seqno made a very large jump on 0x%x delta: %u\n", + ENDPOINT_NUMBER(endp), udelta); + } + } + + /* + * Calculate the jitter between the two packages. The TS should be + * taken closer to the read function. This was taken from the + * Appendix A of RFC 3550. Timestamp and arrival_time have a 1/rate + * resolution. + */ + d = transit - state->stats_transit; + state->stats_transit = transit; + if (d < 0) + d = -d; + state->stats_jitter += d - ((state->stats_jitter + 8) >> 4); + state->stats_max_seq = seq; +} + + + +/** + * The RFC 3550 Appendix A assumes there are multiple sources but + * some of the supported endpoints (e.g. the nanoBTS) can only handle + * one source and this code will patch RTP header to appear as if there + * is only one source. + * There is also no probation period for new sources. Every RTP header + * we receive will be seen as a switch in streams. + */ +void mgcp_patch_and_count(struct mgcp_endpoint *endp, struct mgcp_rtp_state *state, + struct mgcp_rtp_end *rtp_end, struct sockaddr_in *addr, + char *data, int len) +{ + uint32_t arrival_time; + int32_t transit; + uint16_t seq; + uint32_t timestamp, ssrc; + struct rtp_hdr *rtp_hdr; + int payload = rtp_end->codec.payload_type; + + if (len < sizeof(*rtp_hdr)) + return; + + rtp_hdr = (struct rtp_hdr *) data; + seq = ntohs(rtp_hdr->sequence); + timestamp = ntohl(rtp_hdr->timestamp); + arrival_time = get_current_ts(rtp_end->codec.rate); + ssrc = ntohl(rtp_hdr->ssrc); + transit = arrival_time - timestamp; + + mgcp_rtp_annex_count(endp, state, seq, transit, ssrc); + + if (!state->initialized) { + state->initialized = 1; + state->in_stream.last_seq = seq - 1; + state->in_stream.ssrc = state->orig_ssrc = ssrc; + state->in_stream.last_tsdelta = 0; + state->packet_duration = mgcp_rtp_packet_duration(endp, rtp_end); + state->out_stream = state->in_stream; + state->out_stream.last_timestamp = timestamp; + state->out_stream.ssrc = ssrc - 1; /* force output SSRC change */ + LOGP(DMGCP, LOGL_INFO, + "Initializing stream on 0x%x SSRC: %u timestamp: %u " + "pkt-duration: %d, from %s:%d in %d\n", + ENDPOINT_NUMBER(endp), state->in_stream.ssrc, + state->seq_offset, state->packet_duration, + inet_ntoa(addr->sin_addr), ntohs(addr->sin_port), + endp->conn_mode); + if (state->packet_duration == 0) { + state->packet_duration = rtp_end->codec.rate * 20 / 1000; + LOGP(DMGCP, LOGL_NOTICE, + "Fixed packet duration is not available on 0x%x, " + "using fixed 20ms instead: %d from %s:%d in %d\n", + ENDPOINT_NUMBER(endp), state->packet_duration, + inet_ntoa(addr->sin_addr), ntohs(addr->sin_port), + endp->conn_mode); + } + } else if (state->in_stream.ssrc != ssrc) { + LOGP(DMGCP, LOGL_NOTICE, + "The SSRC changed on 0x%x: %u -> %u " + "from %s:%d in %d\n", + ENDPOINT_NUMBER(endp), + state->in_stream.ssrc, rtp_hdr->ssrc, + inet_ntoa(addr->sin_addr), ntohs(addr->sin_port), + endp->conn_mode); + + state->in_stream.ssrc = ssrc; + if (rtp_end->force_constant_ssrc) { + int16_t delta_seq; + + /* Always increment seqno by 1 */ + state->seq_offset = + (state->out_stream.last_seq + 1) - seq; + + /* Estimate number of packets that would have been sent */ + delta_seq = + (arrival_time - state->in_stream.last_arrival_time + + state->packet_duration/2) / + state->packet_duration; + + adjust_rtp_timestamp_offset(endp, state, rtp_end, addr, + delta_seq, timestamp); + + state->patch_ssrc = 1; + ssrc = state->orig_ssrc; + if (rtp_end->force_constant_ssrc != -1) + rtp_end->force_constant_ssrc -= 1; + + LOGP(DMGCP, LOGL_NOTICE, + "SSRC patching enabled on 0x%x SSRC: %u " + "SeqNo offset: %d, TS offset: %d " + "from %s:%d in %d\n", + ENDPOINT_NUMBER(endp), state->in_stream.ssrc, + state->seq_offset, state->timestamp_offset, + inet_ntoa(addr->sin_addr), ntohs(addr->sin_port), + endp->conn_mode); + } + + state->in_stream.last_tsdelta = 0; + } else { + /* Compute current per-packet timestamp delta */ + check_rtp_timestamp(endp, state, &state->in_stream, rtp_end, addr, + seq, timestamp, "input", + &state->in_stream.last_tsdelta); + + if (state->patch_ssrc) + ssrc = state->orig_ssrc; + } + + /* Save before patching */ + state->in_stream.last_timestamp = timestamp; + state->in_stream.last_seq = seq; + state->in_stream.last_arrival_time = arrival_time; + + if (rtp_end->force_aligned_timing && + state->out_stream.ssrc == ssrc && state->packet_duration) + /* Align the timestamp offset */ + align_rtp_timestamp_offset(endp, state, rtp_end, addr, timestamp); + + /* Store the updated SSRC back to the packet */ + if (state->patch_ssrc) + rtp_hdr->ssrc = htonl(ssrc); + + /* Apply the offset and store it back to the packet. + * This won't change anything if the offset is 0, so the conditional is + * omitted. */ + seq += state->seq_offset; + rtp_hdr->sequence = htons(seq); + timestamp += state->timestamp_offset; + rtp_hdr->timestamp = htonl(timestamp); + + /* Check again, whether the timestamps are still valid */ + if (state->out_stream.ssrc == ssrc) + check_rtp_timestamp(endp, state, &state->out_stream, rtp_end, + addr, seq, timestamp, "output", + &state->out_stream.last_tsdelta); + + /* Save output values */ + state->out_stream.last_seq = seq; + state->out_stream.last_timestamp = timestamp; + state->out_stream.ssrc = ssrc; + + if (payload < 0) + return; + + rtp_hdr->payload_type = payload; +} + +/* + * The below code is for dispatching. We have a dedicated port for + * the data coming from the net and one to discover the BTS. + */ +static int forward_data(int fd, struct mgcp_rtp_tap *tap, const char *buf, int len) +{ + if (!tap->enabled) + return 0; + + return sendto(fd, buf, len, 0, + (struct sockaddr *)&tap->forward, sizeof(tap->forward)); +} + +static int mgcp_send_transcoder(struct mgcp_rtp_end *end, + struct mgcp_config *cfg, int is_rtp, + const char *buf, int len) +{ + int rc; + int port; + struct sockaddr_in addr; + + port = is_rtp ? end->rtp_port : end->rtcp_port; + + addr.sin_family = AF_INET; + addr.sin_addr = cfg->transcoder_in; + addr.sin_port = port; + + rc = sendto(is_rtp ? + end->rtp.fd : + end->rtcp.fd, buf, len, 0, + (struct sockaddr *) &addr, sizeof(addr)); + + if (rc != len) + LOGP(DMGCP, LOGL_ERROR, + "Failed to send data to the transcoder: %s\n", + strerror(errno)); + + return rc; +} + +int mgcp_send(struct mgcp_endpoint *endp, int dest, int is_rtp, + struct sockaddr_in *addr, char *buf, int rc) +{ + struct mgcp_trunk_config *tcfg = endp->tcfg; + struct mgcp_rtp_end *rtp_end; + struct mgcp_rtp_state *rtp_state; + int tap_idx; + + /* For loop toggle the destination and then dispatch. */ + if (tcfg->audio_loop) + dest = !dest; + + /* Loop based on the conn_mode, maybe undoing the above */ + if (endp->conn_mode == MGCP_CONN_LOOPBACK) + dest = !dest; + + if (dest == MGCP_DEST_NET) { + rtp_end = &endp->net_end; + rtp_state = &endp->bts_state; + tap_idx = MGCP_TAP_NET_OUT; + } else { + rtp_end = &endp->bts_end; + rtp_state = &endp->net_state; + tap_idx = MGCP_TAP_BTS_OUT; + } + + if (!rtp_end->output_enabled) + rtp_end->dropped_packets += 1; + else if (is_rtp) { + int cont; + int nbytes = 0; + int len = rc; + do { + cont = endp->cfg->rtp_processing_cb(endp, rtp_end, + buf, &len, RTP_BUF_SIZE); + if (cont < 0) + break; + + mgcp_patch_and_count(endp, rtp_state, rtp_end, addr, buf, len); + forward_data(rtp_end->rtp.fd, &endp->taps[tap_idx], + buf, len); + rc = mgcp_udp_send(rtp_end->rtp.fd, + &rtp_end->addr, + rtp_end->rtp_port, buf, len); + + if (rc <= 0) + return rc; + nbytes += rc; + len = cont; + } while (len > 0); + return nbytes; + } else if (!tcfg->omit_rtcp) { + return mgcp_udp_send(rtp_end->rtcp.fd, + &rtp_end->addr, + rtp_end->rtcp_port, buf, rc); + } + + return 0; +} + +static int receive_from(struct mgcp_endpoint *endp, int fd, struct sockaddr_in *addr, + char *buf, int bufsize) +{ + int rc; + socklen_t slen = sizeof(*addr); + + rc = recvfrom(fd, buf, bufsize, 0, + (struct sockaddr *) addr, &slen); + if (rc < 0) { + LOGP(DMGCP, LOGL_ERROR, "Failed to receive message on: 0x%x errno: %d/%s\n", + ENDPOINT_NUMBER(endp), errno, strerror(errno)); + return -1; + } + + /* do not forward aynthing... maybe there is a packet from the bts */ + if (!endp->allocated) + return -1; + + #warning "Slight spec violation. With connection mode recvonly we should attempt to forward." + + return rc; +} + +static int rtp_data_net(struct osmo_fd *fd, unsigned int what) +{ + char buf[RTP_BUF_SIZE]; + struct sockaddr_in addr; + struct mgcp_endpoint *endp; + int rc, proto; + + endp = (struct mgcp_endpoint *) fd->data; + + rc = receive_from(endp, fd->fd, &addr, buf, sizeof(buf)); + if (rc <= 0) + return -1; + + if (memcmp(&addr.sin_addr, &endp->net_end.addr, sizeof(addr.sin_addr)) != 0) { + LOGP(DMGCP, LOGL_ERROR, + "Endpoint 0x%x data from wrong address %s vs. ", + ENDPOINT_NUMBER(endp), inet_ntoa(addr.sin_addr)); + LOGPC(DMGCP, LOGL_ERROR, + "%s\n", inet_ntoa(endp->net_end.addr)); + return -1; + } + + switch(endp->type) { + case MGCP_RTP_DEFAULT: + case MGCP_RTP_TRANSCODED: + if (endp->net_end.rtp_port != addr.sin_port && + endp->net_end.rtcp_port != addr.sin_port) { + LOGP(DMGCP, LOGL_ERROR, + "Data from wrong source port %d on 0x%x\n", + ntohs(addr.sin_port), ENDPOINT_NUMBER(endp)); + return -1; + } + break; + case MGCP_OSMUX_BSC: + case MGCP_OSMUX_BSC_NAT: + break; + } + + /* throw away the dummy message */ + if (rc == 1 && buf[0] == MGCP_DUMMY_LOAD) { + LOGP(DMGCP, LOGL_NOTICE, "Filtered dummy from network on 0x%x\n", + ENDPOINT_NUMBER(endp)); + return 0; + } + + proto = fd == &endp->net_end.rtp ? MGCP_PROTO_RTP : MGCP_PROTO_RTCP; + endp->net_end.packets += 1; + endp->net_end.octets += rc; + + forward_data(fd->fd, &endp->taps[MGCP_TAP_NET_IN], buf, rc); + + switch (endp->type) { + case MGCP_RTP_DEFAULT: + return mgcp_send(endp, MGCP_DEST_BTS, proto == MGCP_PROTO_RTP, + &addr, buf, rc); + case MGCP_RTP_TRANSCODED: + return mgcp_send_transcoder(&endp->trans_net, endp->cfg, + proto == MGCP_PROTO_RTP, buf, rc); + case MGCP_OSMUX_BSC_NAT: + return osmux_xfrm_to_osmux(MGCP_DEST_BTS, buf, rc, endp); + case MGCP_OSMUX_BSC: /* Should not happen */ + break; + } + + LOGP(DMGCP, LOGL_ERROR, "Bad MGCP type %u on endpoint %u\n", + endp->type, ENDPOINT_NUMBER(endp)); + return 0; +} + +static void discover_bts(struct mgcp_endpoint *endp, int proto, struct sockaddr_in *addr) +{ + struct mgcp_config *cfg = endp->cfg; + + if (proto == MGCP_PROTO_RTP && endp->bts_end.rtp_port == 0) { + if (!cfg->bts_ip || + memcmp(&addr->sin_addr, + &cfg->bts_in, sizeof(cfg->bts_in)) == 0 || + memcmp(&addr->sin_addr, + &endp->bts_end.addr, sizeof(endp->bts_end.addr)) == 0) { + + endp->bts_end.rtp_port = addr->sin_port; + endp->bts_end.addr = addr->sin_addr; + + LOGP(DMGCP, LOGL_NOTICE, + "Found BTS for endpoint: 0x%x on port: %d/%d of %s\n", + ENDPOINT_NUMBER(endp), ntohs(endp->bts_end.rtp_port), + ntohs(endp->bts_end.rtcp_port), inet_ntoa(addr->sin_addr)); + } + } else if (proto == MGCP_PROTO_RTCP && endp->bts_end.rtcp_port == 0) { + if (memcmp(&endp->bts_end.addr, &addr->sin_addr, + sizeof(endp->bts_end.addr)) == 0) { + endp->bts_end.rtcp_port = addr->sin_port; + } + } +} + +static int rtp_data_bts(struct osmo_fd *fd, unsigned int what) +{ + char buf[RTP_BUF_SIZE]; + struct sockaddr_in addr; + struct mgcp_endpoint *endp; + int rc, proto; + + endp = (struct mgcp_endpoint *) fd->data; + + rc = receive_from(endp, fd->fd, &addr, buf, sizeof(buf)); + if (rc <= 0) + return -1; + + proto = fd == &endp->bts_end.rtp ? MGCP_PROTO_RTP : MGCP_PROTO_RTCP; + + /* We have no idea who called us, maybe it is the BTS. */ + /* it was the BTS... */ + discover_bts(endp, proto, &addr); + + if (memcmp(&endp->bts_end.addr, &addr.sin_addr, sizeof(addr.sin_addr)) != 0) { + LOGP(DMGCP, LOGL_ERROR, + "Data from wrong bts %s on 0x%x\n", + inet_ntoa(addr.sin_addr), ENDPOINT_NUMBER(endp)); + return -1; + } + + if (endp->bts_end.rtp_port != addr.sin_port && + endp->bts_end.rtcp_port != addr.sin_port) { + LOGP(DMGCP, LOGL_ERROR, + "Data from wrong bts source port %d on 0x%x\n", + ntohs(addr.sin_port), ENDPOINT_NUMBER(endp)); + return -1; + } + + /* throw away the dummy message */ + if (rc == 1 && buf[0] == MGCP_DUMMY_LOAD) { + LOGP(DMGCP, LOGL_NOTICE, "Filtered dummy from bts on 0x%x\n", + ENDPOINT_NUMBER(endp)); + return 0; + } + + /* do this before the loop handling */ + endp->bts_end.packets += 1; + endp->bts_end.octets += rc; + + forward_data(fd->fd, &endp->taps[MGCP_TAP_BTS_IN], buf, rc); + + switch (endp->type) { + case MGCP_RTP_DEFAULT: + return mgcp_send(endp, MGCP_DEST_NET, proto == MGCP_PROTO_RTP, + &addr, buf, rc); + case MGCP_RTP_TRANSCODED: + return mgcp_send_transcoder(&endp->trans_bts, endp->cfg, + proto == MGCP_PROTO_RTP, buf, rc); + case MGCP_OSMUX_BSC: + /* OSMUX translation: BTS -> BSC */ + return osmux_xfrm_to_osmux(MGCP_DEST_NET, buf, rc, endp); + case MGCP_OSMUX_BSC_NAT: + break; /* Should not happen */ + } + + LOGP(DMGCP, LOGL_ERROR, "Bad MGCP type %u on endpoint %u\n", + endp->type, ENDPOINT_NUMBER(endp)); + return 0; +} + +static int rtp_data_transcoder(struct mgcp_rtp_end *end, struct mgcp_endpoint *_endp, + int dest, struct osmo_fd *fd) +{ + char buf[RTP_BUF_SIZE]; + struct sockaddr_in addr; + struct mgcp_config *cfg; + int rc, proto; + + cfg = _endp->cfg; + rc = receive_from(_endp, fd->fd, &addr, buf, sizeof(buf)); + if (rc <= 0) + return -1; + + proto = fd == &end->rtp ? MGCP_PROTO_RTP : MGCP_PROTO_RTCP; + + if (memcmp(&addr.sin_addr, &cfg->transcoder_in, sizeof(addr.sin_addr)) != 0) { + LOGP(DMGCP, LOGL_ERROR, + "Data not coming from transcoder dest: %d %s on 0x%x\n", + dest, inet_ntoa(addr.sin_addr), ENDPOINT_NUMBER(_endp)); + return -1; + } + + if (end->rtp_port != addr.sin_port && + end->rtcp_port != addr.sin_port) { + LOGP(DMGCP, LOGL_ERROR, + "Data from wrong transcoder dest %d source port %d on 0x%x\n", + dest, ntohs(addr.sin_port), ENDPOINT_NUMBER(_endp)); + return -1; + } + + /* throw away the dummy message */ + if (rc == 1 && buf[0] == MGCP_DUMMY_LOAD) { + LOGP(DMGCP, LOGL_NOTICE, "Filtered dummy from transcoder dest %d on 0x%x\n", + dest, ENDPOINT_NUMBER(_endp)); + return 0; + } + + end->packets += 1; + return mgcp_send(_endp, dest, proto == MGCP_PROTO_RTP, &addr, buf, rc); +} + +static int rtp_data_trans_net(struct osmo_fd *fd, unsigned int what) +{ + struct mgcp_endpoint *endp; + endp = (struct mgcp_endpoint *) fd->data; + + return rtp_data_transcoder(&endp->trans_net, endp, MGCP_DEST_NET, fd); +} + +static int rtp_data_trans_bts(struct osmo_fd *fd, unsigned int what) +{ + struct mgcp_endpoint *endp; + endp = (struct mgcp_endpoint *) fd->data; + + return rtp_data_transcoder(&endp->trans_bts, endp, MGCP_DEST_BTS, fd); +} + +int mgcp_create_bind(const char *source_addr, struct osmo_fd *fd, int port) +{ + struct sockaddr_in addr; + int on = 1; + + fd->fd = socket(AF_INET, SOCK_DGRAM, 0); + if (fd->fd < 0) { + LOGP(DMGCP, LOGL_ERROR, "Failed to create UDP port.\n"); + return -1; + } + + setsockopt(fd->fd, SOL_SOCKET, SO_REUSEADDR, &on, sizeof(on)); + memset(&addr, 0, sizeof(addr)); + addr.sin_family = AF_INET; + addr.sin_port = htons(port); + inet_aton(source_addr, &addr.sin_addr); + + if (bind(fd->fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) { + close(fd->fd); + fd->fd = -1; + return -1; + } + + return 0; +} + +int mgcp_set_ip_tos(int fd, int tos) +{ + int ret; + ret = setsockopt(fd, IPPROTO_IP, IP_TOS, + &tos, sizeof(tos)); + return ret != 0; +} + +static int bind_rtp(struct mgcp_config *cfg, const char *source_addr, + struct mgcp_rtp_end *rtp_end, int endpno) +{ + if (mgcp_create_bind(source_addr, &rtp_end->rtp, + rtp_end->local_port) != 0) { + LOGP(DMGCP, LOGL_ERROR, "Failed to create RTP port: %s:%d on 0x%x\n", + source_addr, rtp_end->local_port, endpno); + goto cleanup0; + } + + if (mgcp_create_bind(source_addr, &rtp_end->rtcp, + rtp_end->local_port + 1) != 0) { + LOGP(DMGCP, LOGL_ERROR, "Failed to create RTCP port: %s:%d on 0x%x\n", + source_addr, rtp_end->local_port + 1, endpno); + goto cleanup1; + } + + mgcp_set_ip_tos(rtp_end->rtp.fd, cfg->endp_dscp); + mgcp_set_ip_tos(rtp_end->rtcp.fd, cfg->endp_dscp); + + rtp_end->rtp.when = BSC_FD_READ; + if (osmo_fd_register(&rtp_end->rtp) != 0) { + LOGP(DMGCP, LOGL_ERROR, "Failed to register RTP port %d on 0x%x\n", + rtp_end->local_port, endpno); + goto cleanup2; + } + + rtp_end->rtcp.when = BSC_FD_READ; + if (osmo_fd_register(&rtp_end->rtcp) != 0) { + LOGP(DMGCP, LOGL_ERROR, "Failed to register RTCP port %d on 0x%x\n", + rtp_end->local_port + 1, endpno); + goto cleanup3; + } + + return 0; + +cleanup3: + osmo_fd_unregister(&rtp_end->rtp); +cleanup2: + close(rtp_end->rtcp.fd); + rtp_end->rtcp.fd = -1; +cleanup1: + close(rtp_end->rtp.fd); + rtp_end->rtp.fd = -1; +cleanup0: + return -1; +} + +static int int_bind(const char *port, + struct mgcp_rtp_end *end, int (*cb)(struct osmo_fd *, unsigned), + struct mgcp_endpoint *_endp, + const char *source_addr, int rtp_port) +{ + if (end->rtp.fd != -1 || end->rtcp.fd != -1) { + LOGP(DMGCP, LOGL_ERROR, "Previous %s was still bound on %d\n", + port, ENDPOINT_NUMBER(_endp)); + mgcp_free_rtp_port(end); + } + + end->local_port = rtp_port; + end->rtp.cb = cb; + end->rtp.data = _endp; + end->rtcp.data = _endp; + end->rtcp.cb = cb; + return bind_rtp(_endp->cfg, source_addr, end, ENDPOINT_NUMBER(_endp)); +} + +int mgcp_bind_bts_rtp_port(struct mgcp_endpoint *endp, int rtp_port) +{ + return int_bind("bts-port", &endp->bts_end, + rtp_data_bts, endp, + mgcp_bts_src_addr(endp), rtp_port); +} + +int mgcp_bind_net_rtp_port(struct mgcp_endpoint *endp, int rtp_port) +{ + return int_bind("net-port", &endp->net_end, + rtp_data_net, endp, + mgcp_net_src_addr(endp), rtp_port); +} + +int mgcp_bind_trans_net_rtp_port(struct mgcp_endpoint *endp, int rtp_port) +{ + return int_bind("trans-net", &endp->trans_net, + rtp_data_trans_net, endp, + endp->cfg->source_addr, rtp_port); +} + +int mgcp_bind_trans_bts_rtp_port(struct mgcp_endpoint *endp, int rtp_port) +{ + return int_bind("trans-bts", &endp->trans_bts, + rtp_data_trans_bts, endp, + endp->cfg->source_addr, rtp_port); +} + +int mgcp_free_rtp_port(struct mgcp_rtp_end *end) +{ + if (end->rtp.fd != -1) { + close(end->rtp.fd); + end->rtp.fd = -1; + osmo_fd_unregister(&end->rtp); + } + + if (end->rtcp.fd != -1) { + close(end->rtcp.fd); + end->rtcp.fd = -1; + osmo_fd_unregister(&end->rtcp); + } + + return 0; +} + + +void mgcp_state_calc_loss(struct mgcp_rtp_state *state, + struct mgcp_rtp_end *end, uint32_t *expected, + int *loss) +{ + *expected = state->stats_cycles + state->stats_max_seq; + *expected = *expected - state->stats_base_seq + 1; + + if (!state->stats_initialized) { + *expected = 0; + *loss = 0; + return; + } + + /* + * Make sure the sign is correct and use the biggest + * positive/negative number that fits. + */ + *loss = *expected - end->packets; + if (*expected < end->packets) { + if (*loss > 0) + *loss = INT_MIN; + } else { + if (*loss < 0) + *loss = INT_MAX; + } +} + +uint32_t mgcp_state_calc_jitter(struct mgcp_rtp_state *state) +{ + if (!state->stats_initialized) + return 0; + return state->stats_jitter >> 4; +} |